Record one ditty composed about warmth (8)

I believe the answer is:

tepidity

'warmth' is the definition.
(I know that tepidity is a type of warmth)

'record one ditty composed about' is the wordplay.
'record' becomes 'ep' (abbreviation for extended play record).
'one' becomes 'i' (Roman numeral).
'composed' indicates an anagram.
'about' is an insertion indicator.
'ditty' is an anagram of 'tdity'.
'ep'+'i'='epi'
'epi' inserted inside 'tdity' is 'TEPIDITY'.

I've seen this clue in The Daily Express.

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